<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Markdown</title>
</head>
<style>
    /* .container {
        width: 1000px;
        height: 800px;
        border: 1px solid #ddd;
    } */
    .container-pre {
        width: 1000px;
        height: 800px;
        border: 1px solid #ddd;
        padding: 10px;
    }
</style>
<body>
    <div id="container" class="container" >
        <pre id="container-pre" class="container-pre" contenteditable="true"></pre>
    </div>
</body>
</html>